An organic electronic device (OED) refers to an device including an organic material layer generating a charge flow using holes and electrons, for example, a photovoltaic device, a rectifier, a transmitter, or an organic light emitting diode (OLED).
Among the organic electronic devices, OLEDs have less power consumption and a higher response speed than other light sources, and has advantages in fabricating a thin display device or illuminating device. In addition, since OLEDs have excellent space utilization, OLEDs are expected to be applied to various fields, such as various portable devices, monitors, laptops, and TVs.
The most significant problem in commercialization and pervasive use of OLEDs is durability. Organic materials and metal electrodes included in an OLED may be very easily oxidized by an external factor such as moisture. Accordingly, a product including an OLED may be very sensitive to environmental conditions. Thus, various methods of effectively blocking penetration of oxygen or moisture into an organic electronic device such as an OLED have been proposed. One of those methods is to use an adhesive film.
However, since an existing adhesive film for encapsulating an OLED is formed in a single layer disposed between two release films, adhesion and release properties are very poor. In particular, as the size of the adhesive film increases due to a growth in size of an OLED, a failure rate in peeling of the adhesive film during a process of encapsulating the OLED increases. For example, a peeling failure, such as lifting of the adhesive film, may occur when a protection film or a release film is peeled.
Although release films having different peeling properties have been used, it is not enough to solve the problem.
Accordingly, an adhesive film capable of effectively blocking penetration of moisture, reducing damage to an organic electronic device, and at the same time, reducing defects generated during the process of encapsulating the OLED, needs to be developed.